The present invention relates generally to a process for manufacturing an enclosed transceiver, such as a radio frequency identification (xe2x80x9cRFIDxe2x80x9d) tag.
In the field of radio frequency identification. (xe2x80x9cRFIDxe2x80x9d), communication systems have been developed utilizing relatively large packages whose size is on the order of that of a cigarette package or a substantial fraction thereof, and generally speaking, have been fabricated using hybrid circuit fabrication techniques. These relatively large electronic packages have been affixed, for example, to railroad cars to reflect RF signals in order to monitor the location and movement of such cars.
With respect to an enclosed electronic apparatus, a system for handling baggage in an airport terminal is a typical application. Such a system incorporates radio frequency identification (RFID) between interrogators and transceivers. Further, each baggage tag is an enclosed, battery operated transceiver.
Other smaller passive RFID packages have been developed for applications in the field of transportation, including the tracking of automobiles. These packages include reflective systems of the type produced by Amtech Inc. of Dallas, Tex. However, these reflective passive RFID packages which operate by modulating the impedance of an antenna are inefficient in operation, require large amounts of power to operate, and have a limited data handling capability.
In still other applications of article location and tracking, such as in the postal service or in the field of airline baggage handling and transport, it has not been practical or feasible to use the above relatively large and expensive RFID hybrid packages on smaller articles of transport such as letters, boxed mail shipments or airline luggage. Accordingly, in these latter areas of transport monitoring, as well as many other areas such as inventory control of stored articles, article location and tracking methods have traditionally employed bar code identification and optical character recognition (OCR) techniques which are well known in the art.
Bar code identification and OCR techniques are labor intensive and may, for example, require several airline employees or postal workers to physically manipulate the article and/or the bar code readers to read these bar codes before the transported article reaches its final destination. In addition, the cost of bar code readers and optical character readers is high, limiting the number of locations at which these readers can be used. Furthermore, both bar code readers and optical character readers tend to be highly unreliable.
In yet further and somewhat unrelated fields of: (1) animal tracking and (2) plant tracking, other types of passive RFID tags have been developed by Hughes/IDI/Destron of Irvine, Calif. These tags utilize a coil wrapped around a ferrite core. Such passive RFID tags have a very limited range, on the order of nine (9) inches, have a very limited data handling capability, and are not field programmable. In addition, these tags are limited in data storage capacity and are slow in operation.
In view of the problems described above and related problems that consequently become apparent to those skilled in the applicable arts, the need remains for enclosed electronic apparatus including transceivers wherein the enclosure is inexpensive, readily manufactured in high volume, appropriate in size for use as a stamp, label, or tag, and, in the case of transceivers, operable over distances of several hundred feet without regard for the spacial orientation of the enclosure.
The general purpose and principal object of the present invention is to provide a novel alternative approach to all of the above prior art RFID, OCR, and bar code type location tracking and data storage systems. This new approach as described and claimed herein represents a fundamental breakthrough in the field of article transport control in a wide variety of fields, of which the fields of airline baggage transport, delivery of parcels and mail, and inventory control are only three examples.
To accomplish this purpose and object, we have invented and developed a new and improved radio frequency identification device, an associated electrical system, and a method for communicating with a remote RFID device from a local interrogator and controller. The size of this new device will typically be on the order of one inch square and 0.03 inches thick, or only slightly larger and slightly thicker than a postage stamp. This device includes, in combination, an integrated circuit (IC) which is mounted in an approximately one inch square package and is encapsulated, for example laminated, in a flexible or rigid thin film material. This material may also include a suitable adhesive backing for reliably securing the package to an outer surface or printed label of an article of interest. The IC includes therein a receiver section for driving suitable control logic and memory for decoding and storing input information such as an identification number, the baggage owner""s name, point of origin, weight, size, route, destination, and the like. This memory includes, but is not limited to, PROMS, EPROMs, EEPROMs, SRAMs, DRAMs, and ferroelectric memory devices. The IC also includes a transmitter section therein operative for transmitting this information to an interrogator upon subsequent IC interrogation. An RF antenna is placed in a desired geometrical configuration (for example, monopole, dipole, loop, bow-tie, or dual-dipole) and incorporated within or on the thin film material and adjacent to the IC in an essentially two dimensional structure, neglecting the approximately 30 mil thickness dimension of the completed structure.
Advantageously, a thin battery is connected to the IC for providing power to the IC. The IC also incorporates circuitry to allow for operation in a sleep mode during transit and in storage in order to conserve power. Thus, at shipment points of origin, destination, and locations in transit, an operator may encode data into the IC or interrogate the IC by signaling the IC from a remote location to thereby xe2x80x9cwake upxe2x80x9d the IC without engaging in any hands-on operation.
In a preferred embodiment of the invention, the integrated circuit receiver and transmitter are operated in a spread spectrum mode and in the frequency range of 200 Mhz to 10 GHz, with the range of 800 MHz to 8 GHz being the range of most importance. This operation has the effect of avoiding errors or improper operation due to extraneous signal sources and other sources of interference, multipathing, and reflected radiation from the surrounding environment.
Accordingly, it is a further object of this invention to provide an RPID electronic device of the type described and method of fabricating such device.
Another object of this invention is to provide an RFID system and method of operation of the type described which utilizes RF transmitting and receiving sections on a single IC. Such a system has applications for tracking people or articles in both storage and transit.
Another object of this invention is to provide an electronic device of the type described which does not include bulky hybrid circuits, use modulation techniques described above for passive RFID tags, nor require scanning of bar codes, bar code readers, optical character readers, or especially clean operating environments.
Another object of this invention is to provide an electronic device of the type described which may be manufactured using integrated circuit fabrication and packaging processes.
Another object of this invention is to provide an electronic device of the type described which may be reliably and economically manufactured at high yields and at a high performance to price figure of merit.
Another object of this invention is to provide an RFID device of the type described which is field writable and has a transmission range greater than five (5) feet.
Another object of this invention is to provide a novel assembly process for manufacturing the RFID electronic device described herein.
Another object is to provide a manufacturing process of the type described which is conducive to high speed automation.
Another object is to provide an enclosed electronic device of the type described which is further conducive to high speed product usage, since these RFID devices may be supplied to the customer in a tape and reel format, a fan fold format, or a sheet format.
Another object of this invention is to provide an RFID device of the type described which may be powered with the use of an RP coil and capacitor and without the use of a battery. Such device is also referred to herein as the xe2x80x9cpassivexe2x80x9d device embodiment. However, the term xe2x80x9cpassivesxe2x80x9d refers only to the fact that no battery is used, whereas the electrical circuitry on the IC is indeed active while being powered by the RF coil and capacitor combination.
Another object of this invention is to provide a non-contact method of object and person detection and location which can serve as a replacement for metal-to-metal contact in smart card applications and as a replacement for magnetic strip, bar code, and other types of contact-powered electronics. This novel method of object detection and location represents a significant saving of time and manual effort. For example, consider the time and effort involved when a person must first remove a smart card from a pocket or billfold and then insert the card in a card reader device before being allowed entry into a secured area within a building.
Another object of this invention is to provide an electronic device, system, and communication method of the type described which represents, in novel combination, a fundamental breakthrough in many diverse fields of article shipment, including the parcel post and postal fields, the airline industry, inventory control for many manufacturing industries, security, waste management, personnel, and the like.
Accordingly, an enclosed electrical assembly of the present invention includes: a rigid or flexible thin film support member having an integrated circuit (IC) disposed thereon and an antenna incorporated within the IC or positioned adjacent to the IC within a predetermined area of the thin support member; means on the IC for receiving and encoding data relating to the article being stored or shipped; and means on the IC for reading the stored data and transmitting this data to an operator at a remote location.
According to a first aspect of such an assembly, a base member and a cover member each having conductive patterns developed thereon connect the IC in series with two thin film batteries. By arranging two batteries with the IC, no substantial current flows through a laminated or folded portion of the assembly. Smaller signal levels, lower power operation, and longer useful life of the assembly results.
According to another aspect, antenna coupling is also provided to the IC without current flow through a laminated or folded portion of the assembly. Greater sensitivity in receiving and lower losses in transmitting result.
According to another aspect of the present invention, an RFID device has two modes of operation are provided with a wake-up circuit. The wake-up circuit senses in-band energy and switches from a sleep mode to an operating (waked) mode. The sleep mode being used during transit and storage of the RFID device to conserve battery power.
According to another aspect of such an RFID device, the IC includes receiver and transmitter sections characterized by spread spectrum modulation. Use of spread spectrum modulation reduces data transmission and reception errors, reduces the possibility of improper operation in response to extraneous signal sources, reflected radiation from a surrounding noisy environment, and other interference. Battery power is thereby conserved.
According to another aspect of the present invention, the enclosure includes an adhesive on an outer surface thereof. The adhesive permits reliable and convenient securing of a device of the present invention to an article being transported or stored.
According to yet another aspect of the present invention, by enclosing a transceiver in film, an extremely light weight, durable, and thin package results. Such a package is appropriate for use in replacement of or in conjunction with the conventional handwritten label, conventional hand-cancelled or postage-metered stamp, and the conventional baggage tag.
According to another aspect of the present invention, the frequencies of radio communication, modulation scheme, geometry of the antenna, capacity of the battery, and electrical properties of the enclosure cooperate for omnidirectional communication between an enclosed transceiver of the present invention and a distant interrogator. No manual manipulation of the interrogator or transceiver is required for area-wide communication such as confirming the contents of a delivery vehicle or verifying inventory in place, to name a few examples.
According to an aspect of another embodiment of the present invention, a plurality of transceivers are enclosed and laminated between a pair of films. One side of one of the films has adhesive capability. The transceivers are separated and arranged on a backing. A roll or tape of the backing having transceivers removably attached thereto is enclosed in an RF tight dispenser. The dispenser provide convenient access to unprogrammed transceivers for use on articles to be shipped. When removed from the dispenser, a transceiver communicates with an interrogator in the area for establishing transceiver identity, shipping authorization, destination or storage criteria, date of issue, and similar information. By shielding transceivers within the dispenser from wake-up signals, battery power is conserved.
These and other embodiments, aspects, advantages, and features of the present invention will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art by reference to the following description of the invention and referenced drawings or by practice of the invention. The aspects, advantages, and features of the invention are realized and attained by means of the instrumentalities, procedures, and combinations particularly pointed out in the appended claim.